1. Field of the Invention
This invention relates to runout tables for metal strip mills, and more particularly to an improved containment fence for the runout table of a hot strip finishing mill.
2. Description of the Prior Art
Metal strip produced on a hot strip finishing line is conventionally coiled by coilers spaced a substantial distance from the final stand of the finishing line. A runout table in the form of a driven roller conveyor supports the strip as it moves from the final mill stand to the coiler. The temperature of the strip issuing from the mill is too hot for immediate coiling and must be cooled in its path along the runout table to avoid undesired metallurgical changes in the coil. The high speed and temperature of the strip discharged from the final mill stand may require the coiler to be spaced up to 500 feet, or more, from the final stand even though a large volume of cooling water is applied to both the top and bottom surfaces of the strip in its path along the runout table.
Strip is conveyed along the runout table under low or substantially no tension by the action of the motor driven rollers of the conveyor. In travelling this distance at relatively high speeds, the strip can drift from the center of the conveyor, especially at the free ends of a strip. In the past, a vertically extending plate has been provided at the end of each roller to act as a side guide containing the strip on the conveyor surface. These side guide plates generally were mounted between the end of the roller surface and the supporting bearing and could be mounted on the bearing block itself. These upwardly projecting plates at each end of the rollers cooperated to provide, in effect, a picket-line containment fence along each side of the conveyor path for containing the strip. The individual plates for each roll enabled individual rollers to be removed for service when necessary.
While a containment fence consisting of a series of parallel, closely spaced individual plates projecting upwardly at the end of each roller is effective in containing the strip on the conveyor surface, this arrangement is not entirely satisfactory in that adjacent edges of consecutive plates are not always perfectly aligned. This is particularly true after substantial use because individual plates may become damaged or distorted with the result that a projecting edge can engage the side edge of a hot, fast moving strip. This can produce sufficient damage to interfere with coiling of the strip or even, in severe cases, result in a cobble on the conveyor surface, particularly when the leading end of a strip catches on a fence plate.
A primary object of the present invention is, therefore, to provide an improved containment fence structure for a hot strip mill runout table.
Another object is to provide such an improved containment fence structure which provides ready access to the individual rollers, roller bearings and drive motors of the runout table conveyor while providing a substantially continuous guide fence surface free from any projecting edges capable of engaging and damaging a hot strip edge moving on the table.